Disclosed is a method of producing a soy protein product having a soy protein content of at least 60 wt% (N x 6.25), dry weight basis, which comprises: (a) extracting a soy protein source with an aqueous calcium salt solution to cause solubilization of soy protein from the protein source and to form an aqueous soy protein solution, (b) separating the aqueous soy protein solution from residual soy protein source, (c) concentrating the aqueous soy protein solution while maintaining the ionic strength substantially constant by using a selective membrane technique, (d) optionally diafiltering the concentrated soy protein solution, (e) diluting the concentrated soy protein solution into water to cause the formation of a precipitate, (f) separating the precipitate from the diluting water, termed the supernatant, and (g) optionally drying the separated soy protein precipitate, wherein: (A) the separated soy protein precipitate from step (f) is dried and the dried protein is re-suspended in water, the resulting suspension is adjusted to a pH of 6 if necessary, the suspension is heat treated and either (i) the entire heated suspension is dried to provide the soy protein product or (ii) the insoluble protein is recovered from the heated suspension and the recovered insoluble protein is dried to provide the soy protein product, or (B) the separated soy protein precipitate from step (f) is re-suspended in water and the suspension is heat treated and either (i) the entire heat treated solution is dried to provide the soy protein product or (ii) the insoluble protein is recovered from the heat treated suspension and the recovered insoluble protein is dried to provide the soy protein product.
